Subject: Re: [stella] DASM 'upgrade' in progress From: "Eckhard Stolberg" <Eckhard_Stolberg@xxxxxx> Date: Fri, 21 Mar 2003 22:25:29 +0100 |
>> Any reasons, why the TIA constants start at offset $40? AFAIK in all disassembled old games the registers start at $00. Or is it just to make disassembling with DiStella a bit more compliated? << Andrew is working on a game with Tigervision's 3F bankswitching, where all accesses to addresses $3F and below will trigger the bankswitching logic. Therefore it is nessessary to to use the TIA mirror from $40 up. When I sent this file to Andrew I called it VCS3F.H to differentiate it from the normal VCS.H file. But maybe we should merge both files and add either $00 or $40 to the TIA equates depending on a defined constant? So the VCS.H file would look something like this: IFNCONST TIAOFFSET TIAOFFSET equ $00 ENDIF VSYNC equ $00+TIAOFFSET VBLANK equ $01+TIAOFFSET etc. That way you could do a "TIAOFFSET equ $40" before you include the VCS.H file when you want to write a 3F bankswitched game. If you don't define that value it will default to $00 and all TIA addresses will be normal. Ciao, Eckhard Stolberg ---------------------------------------------------------------------------------------------- Archives (includes files) at http://www.biglist.com/lists/stella/archives/ Unsub & more at http://www.biglist.com/lists/stella/
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